When IMSI is a TBCD-STRING type, and TBCD-STRING is defined as OCTET
STRING, we end up encoding the IMSI the wrong way. I don't knwo why
that is, but changing it fixed the problem, as described below:
before this commit:
00 17 PeranentNAS-UE-ID
40 criticality ignore
0a (length)
00 presence = IMSI
08 BUG: why the additional length field?
46 23 91 34 70 77 80 f3 IMSI (643219430777083)
after this commit:
00 17 PeranentNAS-UE-ID
40 criticality ignore
09 (length)
50 presence = IMSI
46 23 91 34 70 77 80 f3 IMSI (643219430777083)